The Progress MS-05 cargo spacecraft departed the International Space Station on Thursday after a stay of five months facilitating the delivery of 2.4 metric tons of supplies to the orbiting laboratory. Heading toward a fiery re-entry, the spacecraft pulled away from the Station’s Pirs Docking Compartment which will remain vacant until mid-October when the next Progress supply craft is due to arrive at the complex.

Progress MS-05 lifted off from a snow-covered Baikonur Cosmodrome on February 22, riding the final Soyuz U rocket that sailed into retirement after a career of 44 years, holding the record for the longest-serving and most-flown launch vehicle in the history of space flight. Placed into an on-target orbit by the venerable booster, Progress MS-05 completed a two-day link-up with ISS – firing its engine three times before initiating a fully automated rendezvous sequence that included more engine burns to deliver Progress to the vicinity of ISS followed by an automated approach to Pirs.

Soyuz-U sails into Retirement – Photo: Roscosmos

The Progress MS-05 mission delivered a total of 2,398 Kilograms of cargo and supplies to the Space Station comprising the typical mix of food, fuel, maintenance hardware, consumables and water. Over the course of the docked stay, Progress transferred 600 Kilograms of refueling propellant to the Space Station while the crew was tasked with transferring 420kg of water to be used for Oxygen generation and crew consumption. Progress also carried 52kg of pressurized Oxygen to top up the Station’s atmosphere as pressure is regularly lost as the result of spacewalks and vehicle departures.

Dry cargo delivered inside the pressurized compartment of the Progress accounted for 1,326 Kilograms and included 351kg of food provisions, 311kg of maintenance hardware, 130kg of clothing and consumables for the crew, 116kg of hygiene supplies, 78kg of research gear and 159kg of NASA cargo for the Russian crew members. Also aboard the Progress was the first Orlan-MKS space suit (156kg) to reach the International Space Station after the first flight unit was lost in the Progress MS-04 launch failure last December.

Russia’s Orlan Space Suit – Photo: Gagarin Cosmonaut Training Center

Orlan-MKS has been designed to be more robust than its predecessor while being much easier to use and operate, cutting time from the typical preparations flow for each spacewalk carried out on ISS. The suit has been built for up to 20 uses over a service life of six to seven years, capable of supporting extended spacewalks of up to nine hours. Changes to the older suits include the introduction of an automated thermal control system, a suit management computer that controls the temperature & monitors the suit’s life support functions, and a new, more durable material in the suit’s protective outer layers.

Orlan MKS is currently expected to make its debut later this year, potentially as early as August 18 when Cosmonauts Fyodor Yurchikhin and Sergey Ryazansky are expected to venture outside ISS to release a series of five small satellites and complete different outfitting tasks on the exterior of the Russian segment of ISS.

Progress MS-05 was unloaded within a few weeks of its arrival and then took on a new role as the Station’s dumpster, being loaded with no-longer-needed items, trash and liquid waste for eventual disposal via destructive re-entry. Currently the sole Russian crew member on ISS, Fyodor Yurchikhin was tasked with buttoning up the Progress this week – loading the final disposal items before activating the spacecraft, removing air ducts and installing the docking mechanism.

Fyodor Yurchikhin inside Progress MS-05 – Photo: NASA

The hatch of the Progress craft and the Station-side hatch on Pirs were closed on Wednesday for the standard leak check after the vestibule area between the two spacecraft had been depressurized. This ended crew involvement in the Progress mission as all remaining steps were completed under ground commanding, picking up with a re-orientation of ISS on Thursday, pitching over by 90 degrees to point the Progress into the Station’s direction of travel for a standard V-Bar departure along the velocity vector.

With hooks on the Pirs module opened up, Progress powered on its docking mechanism five minutes before departure with hooks on the Progress side starting to drive open 90 seconds prior to undocking to demate the spacecraft.

Loaded springs pushed ISS and Progress apart at 17:46 UTC and the spacecraft drifted away passively for three minutes to open the gap to 20 meters ahead of the departure maneuver. Firing its DPO thrusters, Progress increased its opening rate to be able to move to a safe distance ahead of its deorbit burn.

Photo: NASA TV

Progress MS-05 will only spend a brief period in free flight, opening up a safe gap to ISS before igniting its KTDU-80 main propulsion system at 20:58 UTC for a three-minute retrograde deorbit burn later on Thursday, slowing the craft down by around 100 meters per second to drop out of orbit and meet its fiery fate over the Pacific Ocean. Progress is expected to disintegrate to a large extent with any surviving debris impacting the ocean at around 21:41 UTC to mark the completion of the 158th Progress mission.

The departure of the Progress left ISS with only two visiting vehicles present at the orbiting outpost – the Soyuz MS-04 spacecraft of Expedition 52 Commander Fyodor Yurchikhin and Flight Engineers Jack Fischer and Peggy Whitson; and the Progress MS-06 cargo vehicle docked to the Zvezda module and lending a hand with ISS propulsion and reboost maneuvers, the next of which is planned on August 2.

Teams at the Baikonur Cosmodrome are currently working toward a July 28 launch of the second half of the ISS Expedition 52 crew, Soyuz MS-05 Commander Sergey Ryazansky and Flight Engineers Randy Bresnik and Paolo Nespoli. The next ISS cargo flight will be handled by the SpaceX Dragon, currently targeting liftoff No Earlier Than August 10.